Staff / Principal PLC Controls Engineer

Torrey Holistics; Berkeley (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

Torrey Holistics is seeking a Staff/Principal PLC Controls Engineer to own PLC programming, integration, and commissioning for high-volume test systems. You will work with CODESYS/Structured Text to modify existing logic, implement PLC-to-product-controller communication, and validate updated test stands for production readiness.

You will collaborate across controls, electrical, mechanical, and manufacturing teams to ensure instrumentation, I/O, wiring, and panel functionality meet reliability

Qualifications

• Staff/Principal/SME-level ownership with senior PLC/controls background.
• Expertise in Structured Text and CODESYS in existing codebases.
• Ability to implement PLC-to-controller communication and product-controller integration.
• Strong electrical troubleshooting and system integration capabilities.

Responsibilities

• Develop, modify, debug, and maintain PLC programs using CODESYS/ST.
• Analyze existing PLC code and determine changes for product-controller transition.
• Develop PLC-to-product-controller communication and integration with test stands.
• Verify instrumentation, wiring, I/O, and control-panel functionality during commissioning.
• Collaborate across controls, electrical, mechanical, and manufacturing teams.

Skills

CODESYS

Structured Text

PLC programming

Product-controller integration

Electrical troubleshooting

System integration

Tools

Rockwell/Allen-Bradley

Siemens

Schneider Electric

Mitsubishi

Beckhoff

Modicon

Omron

Job description

Staff / Principal PLC Controls Engineer – Test & IntegrationAbout the RoleWe are seeking a Staff/Principal-level PLC Controls Engineer to take ownership of PLC programming, controls integration, and commissioning for advanced test systems supporting a high-volume manufacturing environment.Why This Role Is OpenThe company is scaling production toward a 225-unit build rate while simultaneously upgrading its test-stand infrastructure and controls architecture.The existing PLC system is functional, but a significant amount of control logic currently resides directly in the PLC. The engineering team is transitioning portions of that functionality into product controllers and needs to establish reliable communication between the PLC and those controllers.This is not a ground-up controls development project. The existing PLC code and functionality are already in place. The immediate need is for an experienced controls engineer who can step into the existing CODESYS/Structured Text codebase, understand how it works, determine what logic needs to be removed or modified, and implement the required PLC-to-controller communication with minimal direction.At the same time, the team is updating its test stands. This engineer will help verify the updated systems before production units arrive, including instrumentation, sensors, PLC I/O, signal scaling, wiring, pinouts, and control-panel functionality.The team is targeting a 225-unit build rate, so they need a true controls SME who can hit the ground running and help move the upgraded test infrastructure into production readiness.What You'll DoDevelop, modify, debug, and maintain PLC programs using CODESYS and Structured Text (ST).Review and understand existing PLC code and control architecture with minimal direction.Identify existing PLC logic that needs to be removed, modified, or transitioned to product controllers.Develop PLC-to-product-controller communication and associated control logic.Integrate product controllers into existing and newly updated test stands.Modify proven PLC functionality while preserving existing system performance and reliability.Troubleshoot PLC logic, I/O, instrumentation, sensors, wiring, pinouts, and control-panel issues.Verify that instrumentation is properly connected to the PLC and that signals are reading, scaling, and outputting correctly.Support electrical troubleshooting during system integration and commissioning.Commission updated test stands and verify system functionality before production units arrive.Work across controls, electrical, mechanical, systems, and manufacturing teams to resolve integration issues.Serve as the controls SME during system integration, commissioning, and production readiness.Identify technical issues quickly, determine root cause, and implement solutions independently.Support improvements to controls architecture, test-system reliability, and production readiness.Document PLC changes, system updates, troubleshooting activities, and commissioning results.Technical EnvironmentCODESYSStructured Text (ST)PLC programming and controls architecturePLC-to-product-controller communicationProduct controllersIndustrial I/OSensors and instrumentationControl panels and electrical systemsAutomated test standsSystem integration and commissioningHigh-volume manufacturing equipmentRequired QualificationsStaff, Principal, or equivalent senior-level PLC/Controls engineering experience.Strong hands-on experience developing and modifying PLC programs.Expert-level experience with Structured Text.Professional experience with CODESYS or a comparable IEC 61131-3 PLC programming environment, with the ability to work directly in CODESYS.Demonstrated ability to enter an existing PLC codebase, understand the logic, and make changes independently.Experience developing communication between PLCs and external/product controllers.Strong understanding of PLC architecture, I/O, instrumentation, sensors, and control systems.Strong electrical troubleshooting skills, including wiring, pinouts, control panels, sensors, and PLC I/O.Experience with system integration, commissioning, or automated test equipment.Ability to troubleshoot problems across both PLC software and physical electrical hardware.Ability to work independently and make technical decisions with minimal supervision.Strong communication and cross-functional collaboration skills.Preferred QualificationsExperience with Rockwell/Allen-Bradley, Siemens, or other industrial PLC platforms.Experience with industrial communication protocols.Experience integrating embedded/product controllers with PLC-based systems.Experience modifying existing PLC architecture rather than developing systems exclusively from scratch.Experience with automated test stands, laboratory equipment, or production test systems.Experience supporting high-volume manufacturing environments.Ability to read and interpret electrical schematics.Experience with instrumentation scaling, signal validation, and I/O commissioning.What We're Looking ForThis role requires more than someone who can troubleshoot a PLC. We need a controls SME who can write code, understand an existing architecture, determine what needs to change, implement the changes, and validate the physical system.The right engineer should be comfortable taking ownership of an existing PLC program and quickly determining:What logic needs to remain.What logic needs to be removed.What functionality needs to move to the product controller.How the PLC should communicate with the product controller.Whether sensors and instrumentation are connected and scaled correctly.Whether wiring, pinouts, I/O, and control-panel connections are functioning correctly.How to diagnose and resolve issues without extensive hand-holding.Recruiter Screening QuestionsPLC / CODESYS / ProgrammingHow much hands-on experience do you have programming PLCs using CODESYS?How strong are you with Structured Text? What percentage of your PLC programming experience has been in Structured Text?Have you inherited an existing PLC codebase and had to understand and modify it with minimal direction? Walk me through an example.Have you removed existing PLC logic and moved that functionality into a separate controller or embedded product controller?Have you developed communication between a PLC and an external controller? What PLCs, controllers, and communication protocols did you use?If given an existing PLC program that is functioning but contains control logic that needs to be removed and replaced with product-controller functionality, how would you approach that change?Integration / CommissioningHave you worked on automated test stands or test equipment? What were you responsible for?Tell me about a commissioning project where you had to verify that sensors or instrumentation were communicating correctly with the PLC.How comfortable are you troubleshooting a sensor that is reading incorrectly, improperly scaled, or not communicating?Can you troubleshoot wiring, pinouts, PLC I/O, and control-panel issues? Give me an example.Have you worked directly with both PLC code and the physical electrical system? Tell me about a problem where you had to troubleshoot both sides.Senior-Level OwnershipHow independently can you operate when entering an unfamiliar PLC codebase?What is the most complex PLC controls system you have personally owned or modified?Have you supported integration and commissioning in a manufacturing or production environment?Are you comfortable operating as the controls SME for a project, making technical decisions and driving issues to resolution without extensive direction?Ideal Candidate ProfileThe strongest candidate will have:CODESYSStructured TextAdvanced PLC programmingPLC-to-controller communicationProduct controller integrationElectrical troubleshootingInstrumentation and sensor integrationPLC I/OControl-panel troubleshootingAutomated test-stand experienceSystem integration and commissioningManufacturing or production environment experienceStaff/Principal/SME-level ownershipSuccess in the RoleSuccess means being able to hit the ground running and take ownership of the controls work without requiring extensive training or direction.The engineer will help transition existing PLC functionality toward product-controller-based control, establish reliable PLC-to-controller communication, integrate updated test stands, and ensure instrumentation and electrical systems function correctly.With the organization targeting a 225-unit build rate, this position has a direct impact on production readiness, test capacity, and the reliability of the manufacturing operation.You should be proficient in:PLC Troubleshooting SkillsElectrical SchematicsSingle and Three Phase Power120/208/240/480 Voltage SystemsIndustrial Robot ProgrammingDesign for Assembly (DFA)PLC Programming ExperienceSCADA ExperienceElectrical / Electronic SystemsHigh Voltage SystemsEquipment Installation & WiringAccess Control SystemsAerospace ManufacturingMachines & technologies you'll use:Variable Frequency Drives (VFD)CAD Software (Solid Edge, Siemens NX, Catia, Pro-E / Creo, NX CAD (Siemens), Solidworks, Onshape, Autodesk Inventor, AutoCAD)Programmable Logic Controller (PLC) (Beckoff, Allen Bradley, Fanuc, Schneider Electric, Mitsubishi, Modicon, Omron, B&R Industrial Automation, Siemens, Panasonic, Sigmatek)Vision SystemServo MotorsIndustrial Robot